Results: 82

Effects of cannabis use on cigarette smoking cessation in LGBTQ+ individuals.
Psychol Addict Behav. 2024 Mar 14;. doi: 10.1037/adb0001001. Epub 2024 Mar 14. PubMed PMID: 38483523;

Effects of mint, menthol, and tobacco-flavored e-cigarettes on tobacco withdrawal symptoms in adults who smoke menthol cigarettes: A laboratory pilot study.
Drug Alcohol Depend. 2024 Mar 1;256:111110. doi: 10.1016/j.drugalcdep.2024.111110. Epub 2024 Jan 25. PubMed PMID: 38359606; PubMed Central PMCID: PMC10906679.

Alcohol use and motives for drinking across the menstrual cycle in a psychiatric outpatient sample.
Alcohol Clin Exp Res. 2023 Jan;47(1):127-142. doi: 10.1111/acer.14971. Epub 2023 Jan 20. PubMed PMID: 36661851; PubMed Central PMCID: PMC9975029.

Interactive effects of financial strain and distress tolerance on prequit tobacco withdrawal symptoms in smokers preparing to initiate a quit attempt.
Exp Clin Psychopharmacol. 2023 Jan 16;. doi: 10.1037/pha0000639. Epub 2023 Jan 16. PubMed PMID: 36649154;

Emotion regulation expectancies and smoking cessation factors: A daily diary study of California adults who smoke cigarettes during a practice quit attempt.
Drug Alcohol Depend. 2023 Feb 17;245:109810. doi: 10.1016/j.drugalcdep.2023.109810. Epub 2023 Feb 17. PubMed PMID: 36857842;

Implementation planning for equitable tobacco treatment services: a mixed methods assessment of contextual facilitators and barriers in a large comprehensive cancer center.
Transl Behav Med. 2023 Mar 20;. doi: 10.1093/tbm/ibac122. Epub 2023 Mar 20. PubMed PMID: 36940412;

Daily ovarian hormone exposure and loss of control eating in adolescent girls: A registered report.
Int J Eat Disord. 2023 Jun;56(6):1246-1253. doi: 10.1002/eat.23962. Epub 2023 Apr 18. PubMed PMID: 37271969;

Associations of DHEA(S) with negative and positive affect in people who smoke daily with elevated and low depression symptoms: A pilot laboratory study.
Addict Behav. 2023 Jul 4;146:107801. doi: 10.1016/j.addbeh.2023.107801. Epub 2023 Jul 4. PubMed PMID: 37423068;

Longitudinal associations between anxiety sensitivity and substance use in adolescents: Mediation by depressive affect.
Exp Clin Psychopharmacol. 2023 Jun 26;. doi: 10.1037/pha0000668. Epub 2023 Jun 26. PubMed PMID: 37358544;

Nicotine deprivation amplifies attentional bias toward racial discrimination stimuli in African American adults who smoke cigarettes.
Exp Clin Psychopharmacol. 2023 Aug 3;. doi: 10.1037/pha0000662. Epub 2023 Aug 3. PubMed PMID: 37535524;

Interactive associations between abstinence plans and romantic partner conflict and support with cigarette smoking.
Drug Alcohol Depend. 2023 Feb 1;243:109756. doi: 10.1016/j.drugalcdep.2022.109756. Epub 2022 Dec 29. PubMed PMID: 36608484;

Effects of 'Ice' flavoured e-cigarettes with synthetic cooling agent WS-23 or menthol on user-reported appeal and sensory attributes.
Tob Control. 2023 Nov 8;. doi: 10.1136/tc-2023-058125. Epub 2023 Nov 8. PubMed PMID: 37940405;

Association of e-Cigarette Use and Postpartum Depression: Pregnancy Risk Assessment Monitoring System 2016-2019.
J Womens Health (Larchmt). 2023 Nov 10;. doi: 10.1089/jwh.2023.0061. Epub 2023 Nov 10. PubMed PMID: 37944112;

Association of depression symptom level with smoking urges, cigarette withdrawal, and smoking reinstatement: A preliminary laboratory study.
Drug Alcohol Depend. 2022 Mar 1;232:109267. doi: 10.1016/j.drugalcdep.2022.109267. Epub 2022 Jan 10. PubMed PMID: 35042097;

Characterizing different-flavored e-cigarette solutions from user-reported sensory attributes and appeal.
Exp Clin Psychopharmacol. 2022 Apr 25;. doi: 10.1037/pha0000563. Epub 2022 Apr 25. PubMed PMID: 35467923;

Affect and subjective cognitive functioning by depression symptom levels during naturalistic cigarette smoking in premenopausal females who smoke daily.
Psychol Addict Behav. 2022 Feb;36(1):90-99. doi: 10.1037/adb0000741. Epub 2021 Apr 12. PubMed PMID: 33844567; PubMed Central PMCID: PMC8505572.

Assessing Sex, Gender Identity, Sexual Orientation, Race, Ethnicity, Socioeconomic Status, and Mental Health Concerns in Tobacco Use Disorder Treatment Research: Measurement Challenges and Recommendations From a Society for Research on Nicotine and Tobacco Pre-conference Workshop.
Nicotine Tob Res. 2022 Mar 26;24(5):643-653. doi: 10.1093/ntr/ntab201. PubMed PMID: 34622932; PubMed Central PMCID: PMC8962699.

Parsing Intra- and Inter-Individual Covariation Between the Sensory Attributes and Appeal of E-Cigarettes: Associations and Gender Differences.
Nicotine Tob Res. 2022 Jun 15;24(7):1012-1019. doi: 10.1093/ntr/ntab255. PubMed PMID: 34891167; PubMed Central PMCID: PMC9199929.

A novel smoking-specific self-control task: An initial study of feasibility, acceptability, and changes in self-control and cigarette smoking behaviors among adults using cigarettes.
Psychol Addict Behav. 2022 Feb;36(1):28-38. doi: 10.1037/adb0000672. Epub 2021 Jun 3. PubMed PMID: 34081484; PubMed Central PMCID: PMC8639834.

Effects of cigarette abstinence on negative and positive affect by depression symptom levels: A lab study.
J Affect Disord. 2022 Jun 15;307:163-170. doi: 10.1016/j.jad.2022.03.052. Epub 2022 Mar 24. PubMed PMID: 35341814;

Understanding daily life experiences of women who smoke: The role of smoking-related weight control expectancies.
Addict Behav. 2022 Nov;134:107413. doi: 10.1016/j.addbeh.2022.107413. Epub 2022 Jun 16. PubMed PMID: 35728423;

Interactions between daily abstinence plans and approach/avoidance motivation on cigarette smoking in pre-quit smokers.
Exp Clin Psychopharmacol. 2022 Oct;30(5):666-672. doi: 10.1037/pha0000473. Epub 2021 Apr 22. PubMed PMID: 36102597;

An analysis of Twitter posts about the U.S. FDA's menthol ban.
Nicotine Tob Res. 2022 Dec 19;. doi: 10.1093/ntr/ntac290. Epub 2022 Dec 19. PubMed PMID: 36534973;

Detecting variations in ovulation and menstruation during the COVID-19 pandemic, using real-world mobile app data.
PLoS One. 2021;16(10):e0258314. doi: 10.1371/journal.pone.0258314. Epub 2021 Oct 20. PubMed PMID: 34669726; PubMed Central PMCID: PMC8528316.

E-cigarette use and promotion by social media influencers during videogame play on Twitch.
Tob Control. 2021 Oct 8;. doi: 10.1136/tobaccocontrol-2021-056828. Epub 2021 Oct 8. PubMed PMID: 34625511; PubMed Central PMCID: PMC9153388.

Electronic Nicotine Delivery Systems (ENDS) Use and Pregnancy I: ENDS Use Behavior During Pregnancy.
Curr Addict Rep. 2021 Sep;8(3):347-365. doi: 10.1007/s40429-021-00380-w. Epub 2021 Jul 13. PubMed PMID: 34513567; PubMed Central PMCID: PMC8425312.

Twitter Posts About Cannabis Use During Pregnancy and Postpartum:A Content Analysis.
Subst Use Misuse. 2021 Apr 6;:1-4. doi: 10.1080/10826084.2021.1906277. Epub 2021 Apr 6. PubMed PMID: 33821757;

Impact of self-efficacy on daily intention to not smoke.
Addict Behav. 2021 Jul;118:106877. doi: 10.1016/j.addbeh.2021.106877. Epub 2021 Feb 22. PubMed PMID: 33714032;

Self-control and smoking in a sample of adults living with HIV/AIDS: A cross-sectional survey.
Addict Behav. 2021 May;116:106807. doi: 10.1016/j.addbeh.2020.106807. Epub 2020 Dec 29. PubMed PMID: 33460989; PubMed Central PMCID: PMC7887055.

Social facilitation of alcohol subjective effects in adolescents: Associations with subsequent alcohol use.
Psychopharmacology (Berl). 2021 Mar;238(3):887-897. doi: 10.1007/s00213-020-05740-4. Epub 2021 Jan 6. PubMed PMID: 33404735;

E-cigarette, cigarette, and cannabis use patterns as a function of sexual identity in a sample of Southern California young adults.
Addict Behav Rep. 2021 Jun;13:100338. doi: 10.1016/j.abrep.2021.100338. Epub 2021 Jan 16. PubMed PMID: 33644294; PubMed Central PMCID: PMC7889792.

Electronic Nicotine Delivery Systems (ENDS) Use and Pregnancy II: Perinatal Outcomes Following ENDS Use During Pregnancy.
Curr Addict Rep. 2021 Sep;8(3):366-379. doi: 10.1007/s40429-021-00381-9. Epub 2021 Jul 21. PubMed PMID: 35368552; PubMed Central PMCID: PMC8974704.

Developmental patterns of tobacco product and cannabis use initiation in high school.
Addiction. 2021 Feb;116(2):382-393. doi: 10.1111/add.15161. Epub 2020 Jul 7. PubMed PMID: 32533801; PubMed Central PMCID: PMC7736052.

Sensory attributes of e-cigarette flavours and nicotine as mediators of interproduct differences in appeal among young adults.
Tob Control. 2020 Nov;29(6):679-686. doi: 10.1136/tobaccocontrol-2019-055172. Epub 2019 Dec 18. PubMed PMID: 31852818; PubMed Central PMCID: PMC7473634.

Sex differences in the appeal of flavored e-cigarettes among young adult e-cigarette users.
Psychol Addict Behav. 2020 Mar;34(2):303-307. doi: 10.1037/adb0000548. Epub 2020 Jan 20. PubMed PMID: 31961168; PubMed Central PMCID: PMC7064389.

Potential Moderating Effects of Sex/Gender on the Acute Relative Reinforcing and Subjective Effects of Reduced Nicotine Content Cigarettes in Vulnerable Populations.
Nicotine Tob Res. 2020 May 26;22(6):878-884. doi: 10.1093/ntr/ntz098. PubMed PMID: 31225625; PubMed Central PMCID: PMC7395666.

Subjective effects of combustible, vaporized, and edible cannabis: Results from a survey of adolescent cannabis users.
Drug Alcohol Depend. 2020 Jan 1;206:107716. doi: 10.1016/j.drugalcdep.2019.107716. Epub 2019 Nov 4. PubMed PMID: 31718923;

Anxiety sensitivity in relation to cigarette smoking and other substance use in African American smokers.
Psychol Addict Behav. 2020 Sep;34(6):669-679. doi: 10.1037/adb0000573. Epub 2020 Mar 12. PubMed PMID: 32162964; PubMed Central PMCID: PMC7483152.

Somatic symptoms and binge eating in women's daily lives.
J Psychosom Res. 2020 Aug;135:110161. doi: 10.1016/j.jpsychores.2020.110161. Epub 2020 May 27. PubMed PMID: 32504896; PubMed Central PMCID: PMC7365755.

Effectiveness of transdermal nicotine patch in premenopausal female smokers is moderated by within-subject severity of negative affect and physical symptoms.
Psychopharmacology (Berl). 2020 Jun;237(6):1737-1744. doi: 10.1007/s00213-020-05494-z. Epub 2020 Mar 10. PubMed PMID: 32157328; PubMed Central PMCID: PMC7244386.

Indirect Associations of Anxiety Sensitivity with Tobacco, Alcohol, and Other Drug Use Problems Through Emotional Disorder Symptoms in Adolescents.
Behav Med. 2020 Apr-Jun;46(2):161-169. doi: 10.1080/08964289.2019.1573797. Epub 2019 Apr 30. PubMed PMID: 31039083; PubMed Central PMCID: PMC6821558.

Conceptualizing Health Behaviors as Acute Mood-Altering Agents: Implications for Cancer Control.
Cancer Prev Res (Phila). 2020 Apr;13(4):343-350. doi: 10.1158/1940-6207.CAPR-19-0345. Epub 2020 Jan 16. PubMed PMID: 31948998; PubMed Central PMCID: PMC7158868.

Impulsivity across substance use categories: Consideration of sex/gender.
Curr Behav Neurosci Rep. 2020 Sep;7(3):109-127. doi: 10.1007/s40473-020-00213-6. Epub 2020 Jul 15. PubMed PMID: 33614396; PubMed Central PMCID: PMC7891462.

Association of frequency of perceived exposure to discrimination with tobacco withdrawal symptoms and smoking lapse behavior in African Americans.
Addiction. 2020 Aug 29;. doi: 10.1111/add.15238. Epub 2020 Aug 29. PubMed PMID: 32860477; PubMed Central PMCID: PMC7914272.

Subjective effects from the first cigarette of the day vary with precigarette affect in premenopausal female daily smokers.
Exp Clin Psychopharmacol. 2019 Aug 1;. doi: 10.1037/pha0000316. Epub 2019 Aug 1. PubMed PMID: 31368771; PubMed Central PMCID: PMC6994325.

Flavored E-cigarette Use and Progression of Vaping in Adolescents.
Pediatrics. 2019 Nov;144(5). doi: 10.1542/peds.2019-0789. PubMed PMID: 31659004; PubMed Central PMCID: PMC6856781.

Effects of non-tobacco flavors and nicotine on e-cigarette product appeal among young adult never, former, and current smokers.
Drug Alcohol Depend. 2019 Oct 1;203:99-106. doi: 10.1016/j.drugalcdep.2019.05.020. Epub 2019 Aug 1. PubMed PMID: 31434028; PubMed Central PMCID: PMC7489757.

Gender Differences in Negative Affect During Acute Tobacco Abstinence Differ Between African American and White Adult Cigarette Smokers.
Nicotine Tob Res. 2019 Jul 17;21(8):1072-1078. doi: 10.1093/ntr/nty122. PubMed PMID: 29917091; PubMed Central PMCID: PMC6636174.

Happiness as a Buffer of the Association Between Dependence and Acute Tobacco Abstinence Effects in African American Smokers.
Nicotine Tob Res. 2018 Sep 4;20(10):1215-1222. doi: 10.1093/ntr/ntx216. PubMed PMID: 29059368; PubMed Central PMCID: PMC6121915.

Ovarian Hormones and Transdermal Nicotine Administration Independently and Synergistically Suppress Tobacco Withdrawal Symptoms and Smoking Reinstatement in the Human Laboratory.
Neuropsychopharmacology. 2018 Mar;43(4):828-837. doi: 10.1038/npp.2017.216. Epub 2017 Sep 14. PubMed PMID: 28905874; PubMed Central PMCID: PMC5809791.

Smoking Consequences Questionnaire: A reevaluation of the psychometric properties across two independent samples of smokers.
Psychol Assess. 2018 May;30(5):678-692. doi: 10.1037/pas0000511. Epub 2017 Aug 7. PubMed PMID: 28782978; PubMed Central PMCID: PMC5803479.

Impulsivity and history of behavioral addictions are associated with drug use in adolescents.
Addict Behav. 2017 Nov;74:41-47. doi: 10.1016/j.addbeh.2017.05.021. Epub 2017 May 24. PubMed PMID: 28570913; PubMed Central PMCID: PMC6604811.

Premenstrual symptoms and factors implicated in smoking cessation among woman smokers.
Exp Clin Psychopharmacol. 2017 Aug;25(4):235-241. doi: 10.1037/pha0000132. Epub 2017 Jul 6. PubMed PMID: 28682101; PubMed Central PMCID: PMC5546922.

Obsessive-compulsive symptoms and negative affect during tobacco withdrawal in a non-clinical sample of African American smokers.
J Anxiety Disord. 2017 May;48:78-86. doi: 10.1016/j.janxdis.2016.10.001. Epub 2016 Oct 5. PubMed PMID: 27769664; PubMed Central PMCID: PMC5380588.

Anhedonia and Abstinence as Predictors of the Subjective Pleasantness of Positive, Negative, and Smoking-Related Pictures.
Nicotine Tob Res. 2017 Jun 1;19(6):743-749. doi: 10.1093/ntr/ntx036. PubMed PMID: 28186553; PubMed Central PMCID: PMC5896550.

Associations of anxiety sensitivity and emotional symptoms with the subjective effects of alcohol, cigarettes, and cannabis in adolescents.
Addict Behav. 2017 Oct;73:192-198. doi: 10.1016/j.addbeh.2017.05.016. Epub 2017 May 18. PubMed PMID: 28544955; PubMed Central PMCID: PMC5515287.

Social Self-Control Is a Statistically Nonredundant Correlate of Adolescent Substance Use.
Subst Use Misuse. 2016 May 11;51(6):788-94. doi: 10.3109/10826084.2016.1141959. Epub 2016 Apr 12. PubMed PMID: 27070833; PubMed Central PMCID: PMC4848138.

Gender, Ethnicity, and Their Intersectionality in the Prediction of Smoking Outcome Expectancies in Regular Cigarette Smokers.
Behav Modif. 2016 Jan;40(1-2):281-302. doi: 10.1177/0145445515608146. Epub 2015 Oct 5. PubMed PMID: 26438665; PubMed Central PMCID: PMC4861042.

Tobacco Withdrawal Amongst African American, Hispanic, and White Smokers.
Nicotine Tob Res. 2016 Jun;18(6):1479-87. doi: 10.1093/ntr/ntv231. Epub 2015 Oct 18. PubMed PMID: 26482061; PubMed Central PMCID: PMC5896798.

Premenstrual symptoms and smoking-related expectancies.
Addict Behav. 2016 Jun;57:38-41. doi: 10.1016/j.addbeh.2016.01.015. Epub 2016 Feb 2. PubMed PMID: 26869196; PubMed Central PMCID: PMC4775430.

Effects of sweet flavorings and nicotine on the appeal and sensory properties of e-cigarettes among young adult vapers: Application of a novel methodology.
Drug Alcohol Depend. 2016 Nov 1;168:176-180. doi: 10.1016/j.drugalcdep.2016.09.014. Epub 2016 Sep 22. PubMed PMID: 27676583; PubMed Central PMCID: PMC5086287.

Associations between ADHD symptoms and smoking outcome expectancies in a non-clinical sample of daily cigarette smokers.
Am J Addict. 2016 Mar;25(2):152-9. doi: 10.1111/ajad.12343. Epub 2016 Feb 12. PubMed PMID: 26871681; PubMed Central PMCID: PMC4920472.

Asians compared to Whites show increased response to d-amphetamine on select subjective and cardiovascular measures.
Pharmacol Biochem Behav. 2016 May;144:73-7. doi: 10.1016/j.pbb.2016.03.003. Epub 2016 Mar 4. PubMed PMID: 26952590; PubMed Central PMCID: PMC4821659.

Negative Urgency Is Associated With Heightened Negative Affect and Urge During Tobacco Abstinence in Regular Smokers.
J Stud Alcohol Drugs. 2016 Sep;77(5):766-73. doi: 10.15288/jsad.2016.77.766. PubMed PMID: 27588535; PubMed Central PMCID: PMC5015468.

Examination of anxiety sensitivity and distress tolerance as transdiagnostic mechanisms linking multiple anxiety pathologies to alcohol use problems in adolescents.
Alcohol Clin Exp Res. 2015 Mar;39(3):532-9. doi: 10.1111/acer.12638. Epub 2015 Feb 23. PubMed PMID: 25706521; PubMed Central PMCID: PMC4411227.

Gender differences in negative reinforcement smoking expectancies.
Nicotine Tob Res. 2015 Jun;17(6):750-4. doi: 10.1093/ntr/ntu226. Epub 2014 Oct 25. PubMed PMID: 25344957; PubMed Central PMCID: PMC4838049.

Novelty Seeking as a Phenotypic Marker of Adolescent Substance Use.
Subst Abuse. 2015;9(Suppl 1):1-10. doi: 10.4137/SART.S22440. Epub 2015 Jun 17. PubMed PMID: 26106262; PubMed Central PMCID: PMC4472033.

The association of SNCA with hazardous alcohol use is mediated by impulsivity.
Psychiatry Res. 2015 Apr 30;226(2-3):523-4. doi: 10.1016/j.psychres.2015.02.011. Epub 2015 Feb 24. PubMed PMID: 25747681; PubMed Central PMCID: PMC4450159.

Relationships between trait urgency, smoking reinforcement expectancies, and nicotine dependence.
J Addict Dis. 2014;33(2):83-93. doi: 10.1080/10550887.2014.909695. PubMed PMID: 24784229; PubMed Central PMCID: PMC4095861.

Depression and anxiety symptoms moderate the relation between negative reinforcement smoking outcome expectancies and nicotine dependence.
J Stud Alcohol Drugs. 2014 Sep;75(5):775-80. doi: 10.15288/jsad.2014.75.775. PubMed PMID: 25208195; PubMed Central PMCID: PMC4161698.

Functional connectivity-based parcellation and connectome of cortical midline structures in the mouse: a perfusion autoradiography study.
Front Neuroinform. 2014;8:61. doi: 10.3389/fninf.2014.00061. Epub 2014 Jun 11. PubMed PMID: 24966831; PubMed Central PMCID: PMC4052632.

Depressive symptoms, negative urgency and substance use initiation in adolescents.
Drug Alcohol Depend. 2014 Nov 1;144:225-30. doi: 10.1016/j.drugalcdep.2014.09.771. Epub 2014 Sep 28. PubMed PMID: 25280962; PubMed Central PMCID: PMC4253553.

Anxiety sensitivity and negative urgency: a pathway to negative reinforcement-related smoking expectancies.
J Addict Med. 2014 May-Jun;8(3):189-94. doi: 10.1097/ADM.0000000000000017. PubMed PMID: 24662369; PubMed Central PMCID: PMC4040151.

Hostility as a predictor of affective changes during acute tobacco withdrawal.
Nicotine Tob Res. 2014 Mar;16(3):335-42. doi: 10.1093/ntr/ntt151. Epub 2013 Oct 10. PubMed PMID: 24113928; PubMed Central PMCID: PMC3920336.

Functional reorganization of motor and limbic circuits after exercise training in a rat model of bilateral parkinsonism.
PLoS One. 2013;8(11):e80058. doi: 10.1371/journal.pone.0080058. Epub 2013 Nov 21. PubMed PMID: 24278239; PubMed Central PMCID: PMC3836982.

Alterations in prefrontal-limbic functional activation and connectivity in chronic stress-induced visceral hyperalgesia.
PLoS One. 2013;8(3):e59138. doi: 10.1371/journal.pone.0059138. Epub 2013 Mar 19. PubMed PMID: 23527114; PubMed Central PMCID: PMC3602545.

Positive and negative affect as predictors of urge to smoke: temporal factors and mediational pathways.
Psychol Addict Behav. 2013 Mar;27(1):262-7. doi: 10.1037/a0031579. PubMed PMID: 23506367; PubMed Central PMCID: PMC3705925.

Sex differences in negative affect and lapse behavior during acute tobacco abstinence: a laboratory study.
Exp Clin Psychopharmacol. 2013 Aug;21(4):269-76. doi: 10.1037/a0033429. Epub 2013 Jul 8. PubMed PMID: 23834551; PubMed Central PMCID: PMC3962304.

Anxiolytic-like effect of pregabalin on unconditioned fear in the rat: an autoradiographic brain perfusion mapping and functional connectivity study.
Neuroimage. 2012 Feb 15;59(4):4168-88. doi: 10.1016/j.neuroimage.2011.11.047. Epub 2011 Dec 1. PubMed PMID: 22155030;

Circadian rhythmicity in serotonin transporter knockout mice.
Life Sci. 2012 Oct 5;91(11-12):365-368. doi: 10.1016/j.lfs.2012.07.018. Epub 2012 Jul 31. PubMed PMID: 22884802;

Functional brain activation during retrieval of visceral pain-conditioned passive avoidance in the rat.
Pain. 2011 Dec;152(12):2746-2756. doi: 10.1016/j.pain.2011.08.022. Epub 2011 Sep 22. PubMed PMID: 21944154; PubMed Central PMCID: PMC3215895.

Mapping functional brain activation using [14C]-iodoantipyrine in male serotonin transporter knockout mice.
PLoS One. 2011;6(8):e23869. doi: 10.1371/journal.pone.0023869. Epub 2011 Aug 23. PubMed PMID: 21886833; PubMed Central PMCID: PMC3160305.